1. Field of the Invention
The invention relates to a down hole well tool having at least two fluid conduits.
2. Description of Related Art
U.S. Pat. No. 4,534,426 (“Hooper”) discloses a packer and pressure differential drilling tool and method of controlled pressure balanced drilling in big hole well bores and shafts. The tool and method are characterized by a large diameter packer slidably engaged with the well bore over a drill bit and through which a dual drill pipe operates and isolates drilling fluid from a hydrostatic head of fluid standing in the well bore surrounding the dual drill pipe. The packer functions as a non-rotatable ram slidable down the well bore and supporting the hydrostatic head and applying weight to the drill bit